In facilities for the receiving and sorting of articles, particularly parcels, packages, and letter, conveyors of various types are provided as part of the sorting system. If an endless belt type conveyor is provided, there will frequently be provided various destinations or discharge stations for packages along each side of predetermined conveyor belt path. Each discharge station may correspond to a particular zip code, for example. Conventionally, sortation of packages is performed by manually removing packages from the belt and placing the packages onto discharge stations.
There are known side-discharge conveyor systems which use a track, formed into a closed loop to support and guide a series of connected carriages. A tiltable tray is conventionally mounted on such carriages for tipping to either side at sort locations. Such a system is disclosed, for example, in U.S. Pat. No. 4,982,828, to Nicolson, et al. However, such systems have a number of disadvantages. The initial cost of constructing the track for such a system is very high. In addition, such systems have numerous mechanical parts, which makes the systems prone to breakdowns as a result of wear on such mechanical parts. Such systems, unlike endless-belt conveyor systems, occupy floor space for a return track. As floor space is typically at a premium in sorting facilities, the need for additional space is a disadvantages of such a system.
There are also known side discharge assemblies which include a belt assembly for supporting a flexible belt, and a member provided for local lateral tilting of the belt assembly. Such a conveyor assembly is disclosed, for example, in U.S. Pat. No. 4,461,378 to Roth. Such a system, like the systems employing carriages on a closed loop, requires a substantial initial investment. In addition, such a system has a large number of moving parts, which are prone to breakdown as a result of mechanical wear.
U.S. Pat. No. 5,388,681 to Bonnet, entitled "Inflatable Conveyor Belt", issued Feb. 14, 1995, discloses a conveyor belt having a lowered surface and a number of articles supporting surfaces, each of which is tiltably attached to the lower surface. Inflatable chambers are defined in the belt, with the article supporting surfaces being disposed to tilt upon inflation of the inflatable members. An article conveyor system includes a belt having a lower surface and article supporting surfaces tiltably attached to the lower surface, a conveyor belt for supporting the belt during motion along a predetermined path, and an apparatus for selectably introducing pressurized air between the lower surface and each of the article supporting surfaces for tilting the article supporting surfaces, thereby causing an article on the selectively tilted article supporting surfaces to be discharged.
Although the above prior art may include advantages, improvements in the art are always needed.